This invention relates to the art of valves and, more particularly, to pressure relief valves. Although the invention will be described with particular reference to a pressure relief valve, it will be recognized that certain features thereof may be used or adapted to use in valves of other types.
Pressure relief valves of a known type include a valve body and a valve bonnet assembled together in a cooperative relationship. The valve body includes an axial inlet port and a lateral outlet port, with an enlarged bore providing communication therebetween. A poppet is slidably guided in the bonnet for movement between open and closed positions for respectively opening and closing the inlet port. A seal ring is positioned in the bore adjacent the inlet port for sealingly surrounding the poppet in its closed position. The seal ring is axially compressed by a retainer ring which is directly engaged by the bonnet itself, and extends completely past the outlet port through the bore so that lateral openings must be provided in the retainer ring to allow flow therethrough from the inlet port to the outlet port. Because of the particular construction involved, the bonnet to valve body seal may not be as effective as desired.
It has, therefore, been considered desirable to develop a new and improved pressure relief valve which would overcome the foregoing difficulty while providing better and more advantageous overall results.